Game of Thrones fans are very serious about uncovering secrets and mysteries hidden in the TV show and the books. Now, one lip-reading fan has figured out Jon Snow’s birth name – And it’s of significant importance. Spoilers ahead.

The finale to HBO’s Game of Thrones season six has revealed plenty of new information regarding character favourite Jon Snow. In one particular scene after his birth atop the Tower of Joy, we see Ned Stark having last words with his dying sister Lyanna Stark. Before her death, however, she leans in close and whispers something important into his ear – something too soft for audiences to make out. Now, one Redditor has uncovered that secret.

According to a post on the subreddit, after doing a bit of lip-reading, user sparkledavisjr has come to the conclusion that Lyanna Stark names her new son’s name is Jaehaerys.

As Redditor sparkedavisjr points out, “what follows appears to be a three syllable word that appears to start with a J. I’m not a great lip-reader, but I’m fairly certain what she says is Jaehaerys.”

Jaehaerys is a Targaryen name.

Jaehaerys I was the 4th Targaryen king to sit the Iron Throne. He was known as “the Wise”, “The Conciliator”, and “the Old King”. His long rule was prosperous and he was aided by his sister-wife Alysanne, who convinced Jaehaerys to expand the Night’s Watch and granted them the land now known as the New Gift.

Jaehaerys II was Jon’s great-grandfather. His reign was short due to his ill-health (only 3 years), but still a good one. Jaehaerys restored stability to the realm, ended the Blackfyre threat during the war of the Ninepenny kings, and improved relations with the major houses who were unhappy during his father’s rule (Aegon V – Egg, the brother of Maester Aemon).

Jon was most likely renamed after Jon Arryn by Ned Stark, who needed to protect the child from Robert Baratheon.

George R.R. Martin’s best-selling book series “A Song of Ice and Fire” is brought to the screen as HBO sinks its considerable storytelling teeth into the medieval fantasy epic. It’s the depiction of two powerful families — kings and queens, knights and renegades, liars and honest men — playing a deadly game for control of the Seven Kingdoms of Westeros, and to sit atop the Iron Throne. Martin is credited as a co-executive producer and one of the writers for the series, which was filmed in Northern Ireland and Malta.